It depends on watering... I grow in smart pots (fabric pots) so there is 2 ways I water when I use the sand...my bigger plants I just suck it up and top feed....takes a little bit longer as you have to wait for the water to filter through the sand...the other method I use (which is way quicker) is to drop my plants into a bucket of water with nutes...since I have fabric pots, the water soaks into the whole root base rather quickly.

It is a pain to water though...not going to lie, but this is a great solution that has worked great for me without using harsh pesticides. Since your pretty close to harvest It should't mess you up too bad.